[Greenbuilding] FW: Question: Water Softeners and Sewer Lagoons

[Lawrence Lile]

An expert at the University of Missouri says that brine from water
softeners is unlikely to upset septic tank systems.  I re-asked the same
question about sewer lagoons and am waiting for a response.  Some
municiplaities don't allow water softener brine in their sewer systems.

 
--Lawrence Lile

________________________________

From: Broz, Robert R. [mailto:BrozR at missouri.edu] 
Sent: Thursday, September 07, 2006 10:24 AM
To: Langford, Dale; Lawrence Lile
Subject: RE: Question: Water Softeners and Sewer Lagoons



Lawrence, 

 

In most every case the brine from a water softener will not harm the
septic tank.  There are several considerations, hardness of the water,
rated capacity of softener (for grains of hardness exchange) and
maintenance on the septic tank.  If your water is extremely hard and has
to back flush too often, it can cause some minor problems but even then,
if the septic tank is properly maintained it should not be an issue with
how the septic tank functions.  

 

Water hardness is measured in milligrams per liter or grains per gallon.


 

                        Milligrams per liter          grains per gallon 

Soft                  0 - 60                            0 - 3.5 

Moderate           61- 120                         3.5 - 7 

Hard                 121 - 180                      7 - 10.5

Very Hard          more than 180               more than 10.5 

 

If your water hardness averages 8 gpg and your softener has a rated
capacity of 20,000 then it should be able to treat 3,000 gallons of
water between regenerations.  This should not create a problem with
brine water entering the septic tank.  

 

The septic tank should be pumped regularly to keep it operating properly
and to reduce the chance of brine causing a problem.  If the solid build
up is too high in the tank it reduces the amount of water available to
dilute the brine water coming in.  Septic tanks should be pumped every
3-5 years depending on family size and water use.  

 

I hope this answers your questions but if you need more information
please contact me.

 

Bob

 

Robert Broz 

Water Quality Specialist

205 Ag Engineering 

Columbia, MO 65211

(573) 882-0085

Fax [573] 884-5650

e-mail brozr at missouri.edu